1. Field of the Invention
The present disclosure relates to position correction apparatuses, liquid ejection apparatuses, and methods for correcting position.
2. Description of the Related Art
For example, an inkjet recording apparatus is known, which forms an image by ejecting ink on a long print sheet from a plurality of nozzles provided in a liquid ejection unit.
In such an inkjet recording apparatus, ink ejection position may shift and in a case where a color image is formed by using a plurality of liquid ejection units, color overlapping accuracy may degraded due to meandering, wrinkle, etc. of the print sheet.
Therefore, a technology is disclosed, in which the liquid ejection units are moved based on conveyance information obtained from print sheet edge position detection results of a plurality of edge sensors, thereby forming the image without unevenness (e.g. Japanese Unexamined Patent Application Publication No. 2010-137489).
According to the technology disclosed in Japanese Unexamined Patent Application Publication No. 2010-137489, the liquid ejection unit is moved so that a relative position of the liquid ejection unit with respect to the print sheet becomes constant by calculating moving speed of the liquid ejection unit based on print sheet shifting speed, thereby forming the image in which unevenness is reduced.
In the liquid ejection unit, image resolution can be improved by forming a plurality of nozzle array in which a plurality of nozzles are arranged in a width direction of print sheet to increase density of nozzles in the width direction. In such a liquid ejection unit, nozzles disposed adjacent to each other in the width direction of the print sheet are separated each other in a conveyance direction of the print sheet. Therefore, in a case where the liquid ejection unit is moved in the width direction according to print sheet edge position during the image forming, dot interval in the width direction of the print sheet may change.